Method and apparatus for flattening cover tape

ABSTRACT

A method and apparatus for flattening cover tape prior to the cover tape being sealed to a carrier tape. The apparatus includes a cover tape flattener with a leading edge angled in the direction of the moving carrier tape and cover tape. The method and apparatus provide for smoothing the cover tape and sealing the cover tape to the carrier tape.

RELATED APPLICATION

[0001] This application claims the benefit of U.S. ProvisionalApplication No. 60/335,560, filed Oct. 31, 2001.

BACKGROUND

[0002] The invention relates to taper machines in which electronic partsare positioned within the compartments of a carrier tape, and in which acover tape is laid over the carrier tape and sealed thereto to trap theparts within the compartments. More specifically, the invention relatesto a method and apparatus for flattening the cover tape prior to thecover tape being sealed to the carrier tape.

SUMMARY

[0003] The present invention provides a flattening mechanism forflattening wrinkles out of cover tape prior to the cover tape beingbonded to carrier tape. The flattening mechanism is biased against thecover tape and includes a leading edge that is angled with respect tothe direction of travel of the cover tape. The leading edge may bedefined by rollers or a plate. As the cover tape moves under theflattening mechanism, the wrinkles are flattened out to edge of thecarrier tape sides. The cover tape is therefore substantially flat orplanar as it is bonded to the carrier tape.

[0004] Other features and advantages of the invention will becomeapparent to those skilled in the art upon review of the followingdetailed description, claims, and drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0005]FIG. 1 is a side elevation view of a taper machine embodying theinvention.

[0006]FIG. 2 is a top plan view of the taper machine.

[0007]FIG. 3 is a perspective view of a portion of carrier tape.

[0008]FIG. 4 is a perspective view of the cover tape flatteningassembly.

[0009]FIG. 5 is a cross-section view taken along line 5-5 in FIG. 2.

[0010]FIG. 6 is a top view of the flattening mechanism in operation.

[0011]FIG. 7 is a cross-section view taken along line 7-7 in FIG. 2.

[0012]FIG. 8 is a top plan view of an alternative flattening mechanismin operation.

[0013]FIG. 9 is a bottom perspective view of the alternative flatteningmechanism.

[0014] Before one embodiment of the invention is explained in detail, itis to be understood that the invention is not limited in its applicationto the details of construction and the arrangements of the componentsset forth in the following description or illustrated in the drawings.The invention is capable of other embodiments and of being practiced orbeing carried out in various ways. Also, it is understood that thephraseology and terminology used herein is for the purpose ofdescription and should not be regarded as limiting. The use of“including” and “comprising” and variations thereof herein is meant toencompass the items listed thereafter and equivalents thereof as well asadditional items. The use of “consisting of” and variations thereofherein is meant to encompass only the items listed thereafter. The useof letters to identify elements of a method or process is simply foridentification and is not meant to indicate that the elements should beperformed in a particular order.

DETAILED DESCRIPTION

[0015]FIGS. 1 and 2 illustrate an inspection, handling, and packagingapparatus 20 that includes a support stand 24, an infeed carrier tapedrive wheel 26, a pick-and-place head or transport 28, a carrier tapeinfeed reel 32 dispensing carrier tape 34, a camera-over-tape or “COT”inspection module 36, a cover tape reel 40 dispensing cover tape 41, acover tape flattening, smoothing, or combing mechanism 42, a sealingshoe 44, a resilient drive roller 48, a backup wheel 50, acamera-after-sealing inspection module or “CASI” module 52, and anoutput reel packaging module 56. The support stand 24 supports aplurality of part input trays 60 that contain parts 64 to be inspectedand packaged. The transport 28 picks the parts 64 off the input trays60, and transfers the parts 64 to the carrier tape 34. The transport 28is preferably a pick-and-place type transport utilizing a vacuum head.

[0016] The carrier tape 34 is best illustrated in FIG. 3, and includes apair of flanges 72 running along its length, and compartments 76 formedbetween the flanges 72. One or both of the flanges 72 may includesprocket holes 80 to facilitate advancing the carrier tape 34 throughthe apparatus 20 and/or other machinery. For example, the infeed carriertape drive wheel 26 may be a pinwheel having sprocket pins that engagethe sprocket holes 80 of the carrier tape 34. The drive wheel 26 may bedriven under power by a motor (not illustrated) to pull the carrier tape34 off the infeed reel 32. Alternatively, the drive wheel 26 may have asmooth or flat surface and/or be passive or not driven by a motor.

[0017] The resilient drive roller 48 rotates under the power of a motor(not illustrated) to pull the carrier tape 34 through the apparatus 20in a downstream direction 82 (an upstream direction being opposite thedownstream direction 82). The flanges 72 of the carrier tape 34 arepinched between the drive roller 48 and the backup wheel 50 tofacilitate the advancement of the carrier tape 34 under the influence ofthe rotating drive roller 48. Alternatively, the drive roller 48 mayinclude pins that engage the sprocket holes 80 in the tape flanges 72 tofacilitate advancing the carrier tape 34 through the apparatus 20. Thecarrier tape 34 is supported at its flanges 72 by guide rails 84 (FIGS.1, 5, and 7) that extend substantially the entire length of theapparatus 20.

[0018] Referring again to FIGS. 1 and 2, the transport 28 places asingle part 64 into each compartment 76 of the carrier tape 34. The COTinspection module 36 is downstream of the transport 28, and includes acamera, which inspects the parts 64 in the carrier tape compartments 76as the carrier tape 34 is advanced through the apparatus 20.

[0019] The cover tape 41 is laid on top of the carrier tape 34downstream of the COT inspection module 36, and is pulled through theapparatus 20 along with the carrier tape 34. The cover tape 41 is guidedfrom the cover tape reel 40 to the carrier tape 34 by a plurality oftensioning rollers 92. The cover tape 41 extends between the flanges 72and completely covers the compartments 76. The adhesive, which is on thecover tape 41 surface, faces the carrier tape 34. Heat activated covertape has adhesive across the complete cover tape surface. Pressuresensitive activated cover tape has only two strips 94 of adhesive (FIG.4) that are located over the flanges 72 of the carrier tape 34. Theadhesive is used to seal the cover tape 41 to the flanges 72 of thecarrier tape 34.

[0020] Referring to FIGS. 1, 2, and 4-6, the flattening mechanism 42 isdownstream 82 of the last tension roller 92 such that both the covertape 41 and carrier tape 34 pass under the flattening mechanism 42. Theflattening mechanism 42 includes a length of spring wire 96, a pair ofroller tubes 100, and a pair of mounting clamps 104. To assemble theflattening mechanism 42, the spring wire 96 is extended longitudinallythrough the roller tubes 100, and the spring wire 96 is then bent intothe shape illustrated. The mounting clamps 104 secure the ends of thespring wire 96 to a support structure 106 alongside the guide rails 84.The resiliency of the spring wire 96 biases the roller tubes 100downwardly against the cover tape 41.

[0021] The spring wire 96 is bent at its center to define a peak thatpoints in the upstream direction. The roller tubes 100 are thereforeangled or swept back from the center of the cover tape 41 in thedownstream direction 82 to the outer edges of the carrier tape 34. Theroller tubes 100, which are preferably made of brass or any othersuitable material, freely rotate about the spring wire 96 as the carriertape 34 and cover tape 41 pass under the flattening mechanism 42. Thebottoms of the roller tubes 100 contact the cover tape 41 and define theleading edge of the flattening assembly 42.

[0022] Referring to FIG. 6, because the roller tubes 100 are angled withrespect to the longitudinal extent of the cover tape 41 and carrier tape34 and with respect to the downstream direction 82, wrinkles in thecover tape 41 are flattened, smoothed, or combed to the edges of thecarrier tape prior to the cover tape 41 and carrier tape 34 moving underthe sealing shoe 44 (i.e., the cover tape 41 is substantially free fromwrinkles downstream 82 of the rollers 100). The flattening mechanism 42therefore helps to maintain the cover tape 41 in a substantially planarcondition immediately prior to the cover tape 41 being bonded to thecarrier tape 34 by the sealing shoe 44.

[0023] Referring now to FIGS. 1 and 7, the sealing shoe 44 isimmediately downstream of, and should be as close as possible to, theflattening mechanism 42. The sealing shoe 44 includes a sealingmechanism 108 that is either a spool-shaped wheel or longitudinal flatshoe. The sealing mechanism 108 has flanges or edges 109 aligned overthe flanges 72 of the carrier tape 34, and in alignment with the linesof adhesive 94 on the cover tape 41 if pressure sensitive adhesive isused. A downward force is applied to the sealing mechanism 108 to pinchthe cover tape 41 and carrier tape 34 together between the sealingflanges 109 and the guide rails 84.

[0024] If heat is required to activate the adhesive, heating elements110 (FIG. 7) may be inserted into the guide rails 84 under the sealingshoe 44 for that purpose. Thus, as the carrier tape 34 and cover tape 41pass under the sealing shoe 44, the adhesive forms a bond (as at 112 inFIG. 6) between the cover tape 41 and the carrier tape 34 to secure thecover tape 41 over the compartments 76 of the carrier tape 34 andthereby trap the parts 64 within the compartments 76.

[0025] Referring back to FIGS. 1 and 2, the CASI module 52 is downstream82 of the sealing shoe 44 and includes a camera that looks down at thetape 34, 41 (substantially as seen in FIG. 6 downstream 82 of therollers 100) and inspects the sealing bonding process for possiblesealing shoe position errors or inconsistent sealing perimeters. Byflattening the cover tape 41 prior to sealing it to the carrier tape 34,the flattening mechanism 42 helps to reduce false rejections by the CASImodule 52. Such false rejections may be caused by the camera of the CASImodule 52 mistaking wrinkles in the cover tape 41 as flaws.

[0026] The loaded carrier tape 34 is then wound onto the outputreel-packaging module 56. The apparatus 20 also includes a processor(not illustrated) that receives information from the COT and CASImodules 36, 52. The processor has memory that records which of the parts64 have been indicated by the inspection modules 36, 52 as having flaws.The flawed tape sealing process or bad parts in tape are later reviewedand, within another operational processes, the good parts 64 are takenfrom the carrier tape 34 for their end use.

[0027]FIGS. 8 and 9 illustrate an alternative construction of theflattening mechanism 42. Similar elements in these drawings are giventhe same reference numerals introduced above. In this construction, thespring wire 96 extends across the cover tape 41 and carrier tape 34substantially perpendicular to the downstream direction 82 and to thelongitudinal extent of the tapes 41, 34, and the rollers 100 arereplaced with a flattening plate 114 having angled edges. The wire 96extends through the flattening plate 114, and the flattening plate 114is pivotal about the wire 96. A pair of set collars 118 are mounted tothe wire 96 on either side of the flattening plate 114 to prevent theflattening plate 114 from sliding along the wire 96, and to maintain theflattening plate 114 over the cover tape 41.

[0028] The flattening plate 114 is angled or swept back from the centerof the cover tape 41 in the downstream direction 82 to the outer edgesof the carrier tape 34, substantially as the rollers 100 in theabove-described first construction are. A cavity 122 is provided in thebottom of the flattening plate 114 to reduce the surface area of theflattening plate 114 that is in contact with the cover tape 41. This inturn reduces the frictional forces applied to the cover tape 41 by theflattening plate 114 and therefore reduces the pulling force required tomove the cover and carrier tapes 41, 34 through the apparatus 20. Theflattening plate 114 operates substantially as described above withrespect to the first construction, except that the leading edge of theflattening plate 114 slides (as opposed to rolling) over the cover tape41 to flatten out wrinkles in the surface of the cover tape 41.

What is claimed is:
 1. A part packaging apparatus for packaging parts ina carrier tape having serially spaced-apart compartments and at leastone flange extending alongside the compartments, and for applying acover tape over the carrier tape, the carrier tape and cover tapetraveling in a downstream direction, the apparatus comprising: a partplacement head adapted to position parts in the carrier tapecompartments; a cover tape applicator for laying the cover tape over thecarrier tape; a flattening apparatus having a leading edge that contactsthe cover tape to smooth the cover tape; and a sealing apparatusdownstream of the flattening apparatus to seal the cover tape to thecarrier tape.
 2. The apparatus of claim 1, wherein the flatteningapparatus includes a tube roller that defines the leading edge and rollsacross the cover tape to smooth the cover tape.
 3. The apparatus ofclaim 1, wherein the flattening apparatus includes at least two tuberollers that each define a leading edge and that together define a peakthat points in an upstream direction.
 4. The apparatus of claim 3,wherein the leading edges are swept back from the peak in the downstreamdirection such that wrinkles in the cover tape are smoothed to the sidesas the cover tape moves downstream.
 5. The apparatus of claim 3, whereinthe peak is centered with respect to the side edges of the cover tape.6. The apparatus of claim 3, wherein the flattening apparatus includes awire that extends longitudinally through the two tube rollers to definean axis of rotation for the rollers, and wherein the flatteningapparatus further includes two mounting clamps securing the ends of thewire to the packaging apparatus, wherein the wire biases the rollertubes into contact with the cover tape.
 7. The apparatus of claim 1,wherein the leading edge extends to the outer edges of the carrier tape.8. The apparatus of claim 1, wherein the flattening apparatus includes aplate that defines the leading edge and that glides across the covertape to smooth the cover tape.
 9. The apparatus of claim 8, wherein theplate includes two edges swept back from the peak in the downstreamdirection and extending to the outer edges of the carrier tape.
 10. Theapparatus of claim 9, wherein a wire extends through the plate such thatthe plate pivots about the wire and wherein the flattening apparatusfurther includes two mounting clamps securing the ends of the wire tothe packaging apparatus, wherein the wire biases the plate into contactwith the cover tape.
 11. The apparatus of claim 8, wherein the plateincludes a cavity on the bottom of the plate to reduce the surface areaof the plate that is in contact with the cover tape.
 12. The apparatusof claim 1, wherein the cover tape is transparent, and the apparatusfurther comprising an inspection module to inspect the part in thecompartment through the cover tape.
 13. A method of smoothing cover tapeand sealing parts in a carrier tape having serially spaced-apartcompartments and at least one flange extending alongside thecompartments, the method comprising: positioning parts in the carriertape compartments; applying the cover tape over the carrier tape;applying pressure on the cover tape with a flattening apparatus having aleading edge as the cover tape travels in a downstream direction;smoothing the cover tape as it travels under the leading edge of theflattening apparatus; and sealing the cover tape to the carrier tape.14. The method of claim 13, wherein sealing the cover tape to thecarrier tape includes applying heat to the carrier tape to activateadhesive on the cover tape.
 15. The method of claim 13, wherein sealingthe cover tape to the carrier tape includes sealing the cover tape tothe carrier tape flange.
 16. The method of claim 13, wherein smoothingthe cover tape includes removing wrinkles from the cover tape.
 17. Themethod of claim 13, wherein smoothing the cover tape includes removingwrinkles from the middle of the cover tape to the outer edges of thecover tape.
 18. The method of claim 13, wherein the flattening apparatusincludes a tube roller, and wherein smoothing the cover tape includesrolling the tube roller across the cover tape to smooth the cover tape.19. The method of claim 13, wherein the flattening apparatus includes aplate, and wherein smoothing the cover tape includes gliding the plateacross the cover tape to smooth the cover tape.
 20. The method of claim13, wherein the cover tape is transparent, and further comprisinginspecting the part in its compartment through the cover tape with aninspection module after the cover tape is sealed to the carrier tape.21. A part packaging apparatus for packaging parts in a carrier tapehaving serially spaced-apart compartments and at least one flangeextending alongside the compartments, and for applying a cover tape overthe carrier tape, the carrier tape and cover tape traveling in adownstream direction, the apparatus comprising: a part placement head toposition parts in the compartments; an inspection module to inspect thepart in the carrier tape compartment; a flattening apparatus including aplate that glides across the cover tape, the plate having a leading edgethat contacts the cover tape to smooth the cover tape, the leading edgeangled in the downstream direction and extending to the outer edges ofthe carrier tape, a wire that extends through the plate such that theplate pivots about the wire, and at least one mounting clamp securingthe end of the wire to the packaging apparatus, wherein the wire biasesthe plate into contact with the cover tape; a sealing apparatus to sealthe cover tape to the carrier tape; and a seal inspection module toinspect the part in the compartment through the cover tape.
 22. Theapparatus of claim 21, wherein the plate includes two leading edges thatdefine a peak that points in an upstream direction.
 23. The apparatus ofclaim 22, wherein the leading edges are swept back from the peak in thedownstream direction such that wrinkles in the cover tape are smoothedto the sides as the cover tape moves downstream.
 24. The apparatus ofclaim 22, wherein the peak is centered with respect to the side edges ofthe cover tape.
 25. The apparatus of claim 21, wherein the plateincludes a cavity on the bottom of the plate to reduce the surface areaof the plate that is in contact with the cover tape.
 26. A partpackaging apparatus for packaging parts in a carrier tape havingserially spaced-apart compartments and at least one flange extendingalongside the compartments, and for applying a cover tape over thecarrier tape, the carrier tape and cover tape traveling in a downstreamdirection, the apparatus comprising: a part placement head to positionparts in the compartments; an inspection module to inspect the part inthe carrier tape compartment; a flattening apparatus including a tuberoller that rolls across the cover tape to smooth the cover tape, thetube roller having a leading edge that contacts the cover tape to smooththe cover tape, the leading edge angled in the downstream direction andextending to the outer edges of the carrier tape, a wire that extendslongitudinally through the tube roller to define an axis of rotation forthe roller, and at least one mounting clamp securing the end of the wireto the packaging apparatus, wherein the wire biases the tube roller intocontact with the cover tape; a sealing apparatus to seal the cover tapeto the carrier tape; and a seal inspection module to inspect the part inthe compartment through the cover tape.
 27. The apparatus of claim 26,wherein the flattening apparatus includes at least two tube rollers thateach define a leading edge and that together define a peak that pointsin an upstream direction.
 28. The apparatus of claim 26, wherein theleading edges are swept back from the peak in the downstream directionsuch that wrinkles in the cover tape are smoothed to the sides as thecover tape moves downstream.
 29. The apparatus of claim 26, wherein thepeak is centered with respect to the side edges of the cover tape.